I have a 31" tube Mitsubishi. The picture has slowly gone to rolling continuously. It is 12 years old. Is this a simple adjustment I can make? There is no mention of this problem in the manual. Do I need to call someone in to fix this? Do I need a new TV. I have moved everything with magnets away from the set.
rsd
Picture "rolling" continuously
Wed, 08/02/2006 - 16:49
#1
Picture "rolling" continuously
RSD, No Im sorry to inform you that there is no vertical hold adjustment with this set. Does the picture roll if you put on the On Screen Menu? If Not then the problem you discribe is most likly around the PIP module, like a bad capacitor or if theres no PIP then itsalso a bad capacitor around where the vert is tken off the Sync separator. If it rolls all the time, no matter what mode your in then the Vertical oscilator has a problem, most likly also a capacitor. This set is 12 years old you said. The capacitors are drying up so It might be a wise thing to put this puppy to bed and get a new upgraded TV. The Estamate is most likly going to cost you 35 to 50 bucks. Try reading http://www.techlore.com/article/10602/g and see if this will help. Good Luck
I am personally attached to my 35MX1 model which was rolling. I found some schematics on line. The deflection circuitry and power supply page shows a pot number VR 402 ,marked Vert. Lin., on the output of IC 401 Vertical Drive. I tweeked it and "Walla" no more rolling. The pot is located on the right side of the center board of the unit and it is a good idea to slide the assembly out with the power OFF for more screw driver clearance.
That control is the vertical linearity, this has nothing to do with vertical hold, most likely you bought yourself more time by adjusting that control. You can do that, by adjusting other controls, you can mask over the real problem. You have to ask yourself "why did it change?". If you as a tech, can't answer that, and you are not sure that changing that control is the correct method. That set just may be on it's way back to your bench real soon, with an angry customer behind it. Larry is probably right, it is a cap somewhere. Caps are notorious for this kind of problem.